Self-priming pump

ABSTRACT

A vertical self-priming pump assembly for unloading bulk cargo carriers is disclosed. The vertical pump has a column which ingests fluid at its lower end and discharges fluid at its upper end. A mixed flow pump is located at the lower end of the column, with multiple turbine pumps located above the mixed flow pump. A poppet valve and a bypass line with a check valve are used for self-priming of the pump. A vent valve and a manual bypass line are provided for initial priming of the pump. Fluid discharged at the upper end of the column passes through a discharge conduit containing a check valve to prevent flow back into the column.

United States Patent 1191 1 51 Apr. 10, 1973 3,434,430 3/1969 Berman eta1. ..415/11 Primary Examiner-C. J. Husar Attorney-Nilsson, Robbins,Wills & Berliner ABSTRACT A vertical self-priming pump assembly forunloading bulk cargo carriers is disclosed. The vertical pump has acolumn which ingests fluid at its lower end and discharges fluid at itsupper end. A mixed flow pump is located at the lower end of the column,with multiple turbine pumps located above the mixed flow pump. Apoppetvalve and a bypass line with a check valve are used for self-priming ofthe pump.

A vent valve and a manual bypass line are provided for initial primingof the pump. Fluid discharged at the upper end of the column passesthrough a discharge conduit containing a check valve to prevent flowback into the column.

4 Claims, 5 Drawing Figures Dicmas 1 SELF-PRIMING PUNIP [75] Inventor:John L. Dicmas, Arcadia, Calif.

[73] Assignee: Johnston Pump Company, Glendora, Calif.

[22] Filed: Apr. 5, 1971 [21] App1.No.: 131,381

52 U.S. c1 ..415/11, 415/353, 417/199 A [51] Int. Cl ..F01b 25/00 [58]Field of Search ..415/1l, 53, 72; 417/199 A; 137/117, 513.5

[56] References Cited UNITED STATES PATENTS 3,078,806 2/1963 Marlowe..415/11 2,902,940 9/1959 Meyer et a1. ..415/11 3,211,102 10/1965 Keehan415/11 3,276,384 10/1966 Boone et a1. 415/11 3,381,618 5/1968 Napolitano..415/l1 1 SELF-PRIMING'PUMP BACKGROUND OF THE INVENTION 1. Field of theInvention This invention relates to pumping devices, and in particularto self-priming pump devices used to unload bulk cargo carriers.

2. Description of the Prior Art A pump used to unload bulk cargo from abarge or tanker must be capable of two stages of operation. First, whenthe vessel has a substantial quantity of cargo, the pump must be capableof pumping large volumes at a high rate. Second, when the vessel isnearly empty, the pump must be capable of stripping the last remainingcargo from the vessel. Hence the pump must be capable of both high andlow volume pumping.

In the past, pumps have been used for unloading bulk cargo from bargeswhich either had a large volume capability but were not efficient forstripping remaining cargo, or which were efficient for stripping butsuffered from low volume capacity. In the present invention, a pump isshown which is capable of very high volume operation, but yet is capableof stripping the last cargo from the vessel. I

In the present invention, there are multiple turbine pumps which givethe pump a large volume flow capability. In combination with the turbinepumps, a single propeller or mixed flow pump is provided which iscapable of pumping a mixture of vapor and fluid. The propeller pump actswith a self-priming valve and an automatic bypass line to providecapability of stripping the last remaining fluid in the vessel. Themixed flow pump and the self-priming and automatic bypass linesdonothinder the high volume flow possible with the multiple turbinepumps. Hence the present invention satisfies both objectives of a pumpto be used for unloading bulk cargo.

SUMMARY OF THE INVENTION The invention comprises a fluid source adaptedto contain a fluid and a column whose lower end ingests fluid from thefluid source. The fluid is discharged at the upper end of the columninto a discharge conduit. A first pump stage is located inside thecolumn near the lower end, and a second pump stage is located inside thecolumn above the first pump stage. A priming valve assembly is connectedto the column downstream of.

the second pump stage. The priming valve assembly allows passage of thefluid from the column into the fluid source when it is open and preventssuch flow when itis closed.

A discharge check valve is located within the discharge conduit. Thedischarge check valve allows flow of the fluid out of the column andthrough the discharge column, but prevents flow in the oppositedirection. An automatic bypass line is connected at one end to thedischarge conduit upstream of the discharge check valve and at the otherend to the fluid source. A bypass check valve is inside the automaticbypass line which prevents flow of the fluid from the discharge conduitto the fluid source through the automatic bypass line but allows for theflow of air from the fluid source to the discharge conduit through theautomatic bypass line.

The novel features which are believed to be characteristic of theinvention, both as to organization and method of operation, togetherwith further objects and advantages thereof will be better understoodfrom the following description considered in connection with theaccompanying drawings in which several preferred embodiments of theinvention are illustrated by way of example. It is tobe expresslyunderstood, however, that the drawings are for the purpose ofillustration and description only and are notintended as a definition ofthe limits of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a front view of oneembodiment of the invention wherein the barrel covers only the lowerportion of the column.

FIG. 2 is a top view of the embodiment of FIG. 1.

FIG. 3 is a front cross-section view of the priming valve assembly.

FIG. 4 is a front cross-section view of the bypass check valve.

FIG. 5 is a front view of an embodiment of the invention wherein thebarrel covers nearly the entire column.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to FIG. 1, anembodiment of the pump assembly which might be used in a tanker whereinthe fluid is kept at a lower level than the deck of the vessel isillustrated. A fluid 10 which is stored in a fluid supply 12 is free topass through an inlet 14 to the barrel 16 which acts as a fluid sourceto the column 18. The fluid 10 is ingested into the column 18 at itslower end 20. To facilitate entry of the fluid 10 into the lower end 20of the column 18, the lower end may be flared as shown in the figure.

A first pump stage 22 is located near the lower end 20 of the column 18.The first pump stage 22 is a mixed flow or propeller type pump which iscapable of pumping mixtures of the fluid l0 and vapor which might enterthe first pump stage 22 when it is not fully primed. Downstream of thefirst pump stage 22 is a second pump stage consisting of multipleturbine pumps 24 and 26. The fluid 10 is ingested into the lower end 20of the column 18, and is then impelled upward through the column 18 bythe first pump stage 22 and then the multiple turbine pumps 24 and 26.

The fluid 10 passes out the upper end 28 of the column 18 into adischarge conduit 30. A discharge check valve 32 is located in thedischarge line 30. The discharge check valve 32 can be of the typeindicated in FIG. 1 wherein a disc 34 is pivoted about a point 36 nearthe edge of the disc 34. When the fluid is passing through the dischargeconduit 30 in the normal manner out of the column 18 as indicated by thearrow 38, the disc 34 pivots up out of the path of the fluid 10 and doesnot impede that flow. However, if the fluid 10 is moving in the oppositedirection (not shown) through the discharge conduit 30 into the column18, the disc 34 pivots down to abut a ring 40 as indicated in FIG. 1 toseal the discharge column 30 and prevent such flow.

Referring still to FIG. 1, a priming valve assembly 42 is connected tothe column 18 just downstream of the multiple turbine pumps 24 and 26.In the embodiment shown, the priming valve assembly 42 is located abovethe barrel 16. The priming valve assembly 42 is adapted so as to allowflow of the fluid from the column 18 into the barrel 16.when the firstpump stage 22 is unprimed. However, when the pump assembly is in normaloperation, the priming valve assembly 42 prevents flow between thecolumn 18 and the barrel 16 through the priming valve assembly 42.

An automatic bypass line 44 is connected to the discharge conduit 30upstream of the discharge check valve 32 at one end and to the barrel 16at the other end. A bypass check valve 46 is located on the automaticbypass line 44. The bypass check valve 46 operates to prevent flow ofthe fluid 10 from the discharge conduit 30 to the barrel 16 through theautomatic bypass line 44, but allows air or vapor to pass from thebarrel 16 to the discharge column 30.

A vent valve 48 is provided on the discharge column 30. The vent valve48 is normally closed, but can be opened manually to remove air from thedischarge column 30 for manual priming when desired.

In the embodimentshown in FIG. 1, a motor 50 is provided with an outputshaft 52 to drive the first pump stage 22 and the multiple tui'binepumps 24 and 26. The output shaft 52 extends through the column 18 tothe pump stages to rotate those stages. The entire device is shown inrest on a flat plate 54 which rests on the deck ,56 or other structureof the vessel to be unloaded. The column 18 passes through a hole 58 inthe deck 56 to reach the cargoarea.

Refer-ring to FIG. 2, a top view of the pump assembly shown in FIG. 1 ispresented. In this view, the position of the discharge conduit30 withthe discharge check I I valve 32'relative to the motor 50 and the flatplate 54 is indicated. The location of the bypass check valve 46 on theautomatic bypass line 44 can easily be seen in this view. The positionof the vent valve 48 on the discharge conduit 30 is also apparent. Theflow of fluid through the discharge'conduit 30 during normal operationof the pump is indicated bythe arrow 38.

, v In FIG. 2, the manual bypass line 60 which could not be seen in FIG.1 is shown. The manual bypass line 60 is .c'onnectedto the dischargeconduit 30 upstream of the discharge check valve 32 at one end anddownstream ,of the discharge check valve 32 at the otherend. A

manual bypass valve 62 is located on the manual bypass line 60. .Themanual bypass valve 62is closed during normal operation of the pumpassembly, but may b opened manually for initial priming.

' Referring to FIG. 3, the priming valve assembly 42 is illustrated indetail; The priming valve assembly 42 is attached to the column 18 atone end and to the barrel 16 at the other end. The priming valveassembly 42 lllustratedis of the poppettype, having a head 70 attachedto a slidable stem 72 which acts to seal off a port 74. The head 70 ofthe valve'is biased in its open position denotedby the dashed line 76 bya helical spring 78. The helical spring 78 surrounds the slidable stem72 and the flexing of the helical spring 78 about its longitudinal axisacts to bias the head 70 in the open position The helical spring 78abuts a movable plate 80 which is attached to a set screw 82. The setscrew 82 is threaded into the structure of the valve 84 such thatrotation of the set screw 82 moves the movable plate 80 along thelongitudinal axis of the helical spring 78. By adjusting the position ofthe set screw 82, the compression on the helical spring 78 required toclose the valve head 70 can be adjusted. A removable cap 86 is placedover the set screw 82 to protect the set screw but which can easily beremoved for access to the set screw 82 for adjustment. Removal of thecap 86 also provides ready access to the stem 72 so that it may bemanually manipulated. This feature has been found to be extremelyimportant. If a valve such as the priming valve 42 is not used for along period of time it sometimes sticks. Prior art valves requireextensive dismantling of the pump structure to reach the priming valve.

The bypass check valve 46 is illustrated in detail in FIG. 4. The bypasscheck valve 46 is located on the automatic bypass line 44. The bypasscheck valve 46 shown has a disc 90 which is pivoted about a point 92near the edge of the disc 90. An arm 94 is connected to the disc 90'near the center of the disc at one end, and is pivotable about the pivotpoint 92. When the pump assembly is in normal operation, fluid entersthe automatic bypass line 44 as indicated by the arrow 96. Movement ofthe fluid in this manner causes the disc 90 I to be pivoted downward andto abut against the annular ring 98, which seals the automatic bypassline 44 and preventsflo'w of fluid in the direction 96.

When the pump assembly loses prime fluid will not be pumped in thedirection 96. Lack of fluid pressure on the right side (asviewed in FIG.4) of the disc 90 will allow it to be pivoted upward by the force ofairpressure from the barrel 16 in the opposite direction.

The disc will pivot out of the flow of air and willnot restrict suchflow.

Referring to FIG. 5, embodimentof-the pump assembly which might be usedwith a 'bargewhere the cargo fills all of the area below the deck isillustrated. In this embodiment, the barrel covers almost the entirelength of the column 102. The primingvalve assembly 104 is locatedwithin the barrel 100,-but still provides a means for fluid to flow fromthe column 102 above the multiple turbine pumps 106 and 108 into the adischarge check valve 122 which prevents flow of the fluid from thedischarge conduit back into the column 102. An automatic bypass line124havinga bypass check valve 126 is attached to the discharge conduit120 at one end and the barrel 100 at the other end which permits flow ofair from the barrel 100 to the discharge conduit 120 but prevents flowof fluid 114 from the discharge conduit 120 to the barrel 100.

The pump assembly is driven by a motor 128 having a drive shaft 130which rotates the multiple turbine pumps 106 and 108 and the first pumpstage 110. The pump assembly rests on a flat plate 132 mounted on thedeck 134 or other structure of the vessel which is to be unloaded.

The operation of the pump assembly can be easily demonstrated from theabove illustrations. In normal operation, fluid enters the barrel 16from a fluid source 12. The fluid 10 is ingested into the lower end 20of the column 18, impelled upward through the column by the first pumpstage 22 and the multiple turbine pumps 24 and 26. The fluid 10 isdischarged at the upper end 28 of the column 18 into a discharge conduit30. The first pump stage 22 and the multiple turbine pumps are driven bya motor 50.

In normal operation of the pump assembly, the priming valve assembly 42,the bypass check valve 46, the vent valve 48 and the manual bypass valve62 are closed. The discharge check valve 32 is open to allow free flowof the fluid 10 through the discharge conduit 30.

When the level of the fluid 10 in the barrel 16 falls below the lowerend 20 of the column 18, the first pump stage 22 loses prime. When thisoccurs, the multiple turbine pumps 24 and 26 will also lose prime, andthe normal flow of fluid 10 will stop. When the normal flow of fluid 10stops, the pressure difference between the column 18 and the barrel 16which held the priming valve assembly 42 in the closed position willdecrease, allowing the priming valve assembly to open. With the primingvalve assembly 42 open, the fluid 10 can flow back from the column 18into the barrel 16 to reprime the first pump stage 22.

' When the fluid flow through the discharge conduit 30 is stopped, thedischarge check valve 32 closes to prevent fluid which has already beenpumped from reentering the column 18. To prevent a formation of a vacuumin the discharge column 30, an automatic bypass line 44 is provided. Theautomatic bypass line 44 has a bypass check valve 46, but this valveallows air to pass from the barrel 16 to the discharge column 30 toprevent formation of a vacuum and facilities flow to fluid 10 to primethe first pump stage 22.

The pump assembly is provided with two methods of initial priming of thepump manually. The vent valve 48 may be opened which allows fluid 10which is in the column 18 to flow into the barrel 16 for priming. Thevent valve 48 is operated manually, and eliminates the vacuum whichretains the fluid in the column 18. The pump assembly may be also primedwith fluid 10 in the discharge conduit 30 upstream of the dischargecheck valve 32. The manual bypass valve 62 may be opened to allow fluidin the discharge conduit 30 upstream of the discharge check valve 32 toflow through the manual bypass line 60. In this manner the fluid 10 isallowed to flow back into the column 18 to prime the pump assembly.

I claim:

1. A pump assembly comprising:

a barrel adapted to contain a fluid,

an inlet to the barrel adapted to allow ingestion of the fluid from afluid supply into said barrel,

a column having a lower end adapted to ingest the fluid from the barreland an upper end adapted to discharge said fluid,

a mixed flow pump interior the column adjacent the lower end of saidcolumn adapted to pump a mixture of the fluid and vapor,

multiple turbine pumps interior downstream of the mixed flow pump,

a priming valve including a poppet valve assembly having a first endconnected directly to an opening the column in the column downstream ofthe multiple turbine pumps and a second end leading into the barrel,said poppet valve assembly adapted to allow passage of the fluid fromthe column into the barrel when open and to prevent passage of saidfluid from the column into said barrel when closed, said poppet valveassembly adapted to be held in the closed position by greater pressurein said column relative to pressure in said barrel,

means for biasing the poppet valve assembly to the open position,

a discharge conduit connected to the upper end of the column and adaptedto receive the fluid discharged therefrom,

a discharge check valve located in the discharge conduit and adapted toprevent flow of the fluid through said discharge conduit into the columnand permit flow of said fluid out of said column through said dischargeconduit,

an automatic bypass line having a first end connected to the dischargeconduit upstream of the discharge check valve and a second end connectedto the barrel,

and

a bypass check valve interior the automatic bypass line and adapted toprevent flow of the fluid from the discharge conduit to the barrelthrough the automatic bypass line and adapted to allow flow of air fromthe barrel to the discharge conduit through the automatic bypass line.

2. A device as recited in claim 1 and additionally comprising:

a manual bypass line having a first end connected to the dischargeconduit upstream of the discharge check valve and a second end connectedto the discharge conduit downstream of the discharge check valve,

a manual bypass valve interior the manual bypass line and adapted toallow passage of the fluid through the manual bypass line when open andadapted to prevent passage of the fluid through said manual bypass linewhen closed,

and

a vent valve located on the discharge conduit upstream of the dischargecheck valve and adapted to remove air from said column when open.

3. A device as recited in claim 1 wherein the means for biasing thepoppet valve assembly to the open position comprises:

a spring adapted to bias the poppet valve assembly to the open position,and means for adjusting the compression of the spring.

4.A device as recited in claim 3 wherein the spring is a helical springadapted to flex along its longitudinal axis and wherein the means foradjusting the compression of the spring comprises:

a movable plate adapted to abut the helical spring and move along thelongitudinal axis of said helical spring,

a set screw connected to the movable plate and adapted to move saidmovable plate along the longitudinal axis of the helical spring whensaid set screw is rotated,

and

a removable cap adapted to fit over and protect the set screw andadapted to be removed.

1. A pump assembly comprising: a barrel adapted to contain a fluid, aninlet to the barrel adapted to allow ingestion of the fluid from a fluidsupply into said barrel, a column having a lower end adapted to ingestthe fluid from the barrel and an upper end adapted to discharge saidfluid, a mixed flow pump interior the column adjacent the lower end ofsaid column adapted to pump a mixture of the fluid and vapor, multipleturbine pumps interior the column downstream of the mixed flow pump, apriming valve including a poppet valve assembly having a first endconnected directly to an opening in the column downstream of themultiple turbine pumps and a second end leading into the barrel, saidpoppet valve assembly adapted to allow passage of the fluid from thecolumn into the barrel when open and to prevent passage of said fluidfrom the column into said barrel when closed, said poppet valve assemblyadapted to be held in the closed position by greater pressure in saidcolumn relative to pressure in said barrel, means for biasing the poppetvalve assembly to the open position, a discharge conduit connected tothe upper end of the column and adapted to receive the fluid dischargedtherefrom, a discharge check valve located in the discharge conduit andadapted to prevent flow of the fluid through said discharge conduit intothe column and permit flow of said fluid out of said column through saiddischarge conduit, an automatic bypass line having a first end connectedto the discharge conduit upstream of the discharge check valve and asecond end connected to the barrel, and a bypass check valve interiorthe automatic bypass line and adapted to prevent flow of the fluid fromthe discharge conduit to the barrel through the automatic bypass lineand adapted to allow flow of air from the barrel to the dischargeconduit through the automatic bypass line.
 2. A device as recited inclaim 1 and additionally comprising: a manual bypass line having a firstend connected to the discharge conduit upstream of the discharge checkvalve and a second end connected to the discharge conduit downstream ofthe discharge check valve, a manual bypass valve interior the manualbypass line and adapted to allow passage of the fluid through the manualbypass line when open and adapted to prevent passage of the fluidthrough said manual bypass line when closed, and a vent valve located onthe discharge conduit upstream of the discharge check valve and adaptedto remove air from said column when open.
 3. A device as recited inclaim 1 wherein the means for biasing the poppet valve assembly to theopen position comprises: a spring adapted to bias the poppet valveassembly to the open position, and means for adjusting the compressionof the spring.
 4. A device as recited in claim 3 wherein the spring is ahelical spring adapted to flex along its longitudinal axis and whereinthe means for adjusting the compression of the spring comprises: amovable plate adapted to abut the helical spring and move along thelongitudinal axis of said helical spring, a set screw connected to themovable plate and adapted to move said movable plate along thelongitudinal axis of the helical spring when said set screw is rotated,and a removable cap adapted to fit over and protect the set screw andadapted to be removed.